Stay-bolt.



J. SOHMITT.

STAY BOLT.

APPLICATION FILED MAR.20,1912.

Patented Feb. 4, 1913.

I 9 a) fllizvn gj,

UNITED STATES PATENT OFFICE.-

JULIUS somrrr, or MINNEAPOLIS, mmnnso'ra.

Patented Feb. 4,-1913.

STAY-BOLT.

1,052,282. Specification of Letters Patent.

Application nieaxareh 26, 1912. Serial no. 685,105.

To all whom it may concern:

Be it known that I, JULIUs sonmrrnof Minnea olis, in the county ofHennepin and State 0 Minnesota, have invented a certain new and usefulImprovement in Stay-Bolts;

and I do hereby declare the following to be a full and exactv butconcise description ofmy invention,'which I believe is a decidedimprovement over stay-bolts because of its.

simplicity in its construction and durability in its use. p

My invention has for its object to provide -an improved stay-bolt, andto this end, it

consists of the novel devices and combinations of devices, hereinafterdescribed and defined in the claims.

, -The invention is inuaeted the single view of the accompanyingdrawing.

Referring to the drawing, the single figure is a view partly in plan andpartly 1n horizontal section, showing three of the improved stay-boltsapplied to the inner and outer. sheets of a fire box and each thereofshowing a different step required in securing the same to the saidsheets.

The numeral 1 indicates the outer sheet of the fire box, and the numeral2 indicates the inner sheetthereof. These two sheets 1'.

eimproved stay-bolt'is indicated as an entirety by the numeral '5. Atits extreme outer ends, the stay-bolt 5 is provided with an angularportion-6 to which a wrench ,may be applied for screwing-the stay-bolt 5into engagement with the sheets 1 and 2.

Inward o this angular portion 6, the stayb0lt'5 is provided with a screwthreaded portion 7 the screw threads of which are adapted to registerwith the screw threads of the openings 3. At its extreme inner end, thestay-bolt 5 is circumferentially reduced at 8 to afford a stopshoulder 9adapted to be forced into engagement with the inner face of the sheet 2under the rotary movement of the stay-bolt 5 at the time the same isapplied to the sheets 1 and 2. The reduced ortion 8 is provided withscrew threads t at are adapted to register with the screw threads of theopening 4 that is axially alined with the opening 3 into which the screwthreaded portion 7 of the staybolt is mounted. Inward of the stopshoulthe so. 56M 5 to t e sheets 1 an der 9, the stgybolt 5 is providedwith a screw thread portiOn lO of the same diameter as the screwthreaded portion .7.-

the same reversed directionstoward the Y axis of the stay-bolt 5.

- The stay-bolt 5 at the left in the drawing shows "1h? finished.'roduct.';In a "plyin 2, the

screwt readed portion -10 is first screwed completely through one of theopenings 3.

After this is done, the intermediate section 11 is free to be movedendwise 'coinpletely throu h the opening 3. Next the screw threadedportion 7 is screwed into the opening 3 to an extent suflicient to bringthe stop shoulder 9 into tight engagement with the sheet 2. During thissame operation, the reduced portion 8 is screwed into the opening 4. p lAfter thestay-bolt 5-is secured into position to the sheets land 2, itsouter or front end portion is cut off, as shown by the intermediatestay-bolt 5. The cutting off of the frontjend of thestaybolt 5 may beaccomplished by any suitable tool, not shown, or it may be done in'thecustomary manner of reducing or weakening the stay-bolt at the time thesame is manufactured and at a point where it is desired to cut the sameoff of the stay-bolt 5 to be twisted off by a continued movement of theapplied wrench after the stop shoulder 9 has been firmly seated againstthe sheet 2.

The next and final operation in securing the stay-bolt 5 to the'sheets 1and 2 is to upset the front and rear rojecting ends thereof to form,respectivel rivet heads 7 and 8'. Obviously, the shoulder 9 and rivethead 8 securely hold the sheet 2 against the action of the heat and alsoprevent any leakage from the boiler into the fire box. It is alsoevident that by providing the portion 10 of the stay-bolt 5 with screwheads, the maximum width to the stop shoulder 9 is given. By reducingthe diameter of the stay-bolts 5 at their intermediate portions,

'the danger of breakage due to the expansion verse directionsinward-toward the axis ofthe stay-bolt, and theouter projecting ends ofsaid stay-bolt being upset against the said two sheets toeform rivetheads.

2. A stay-bolt havin relatively large and relatively small screw treaded end portions adapted to be screwed respectively into,

screw threaded openings in the outer and inner sheets of a fire box,said stay-bolt inward of its relatively small screw threaded 'ortionbein increased in diameter to aford a stop s oulder adapted to engagewith said inner'sheet, said increased portion of said stay-bolt havingscrew threads of the same diameter as the said relatively large screwthreaded end portion of said stay-bolt.

3. A stay-bolt having relatively large and relatively small screwthreaded end' portions adapted to be screwed respectively into screwthreaded openings in the outer and inner sheets of a fire box, Saidstaybolt 1nward of its relatively small screw threaded portion beingincreased in diameter to atford a stop shoulder adapted to engage withsaid inner sheet, said increased portion of said stay-bolt having screwthreads of the same diameter as the said relatively large screw threadedend portion of said stay-bolt, the intermediate portion of saidstay-bolt being tapered in reverse directions inward toward the axis ofsaid stay-bolt.

JULIUS SCHMITT.

Witnesses:

J. S. (30001;, O. J. SMITH.

